The proposed five-phase program of research is designed to investigate the nature, generality, and developmental course of "intelligence", focusing on the role of knowledge and context in shaping cognitive performance. In PHASE 1 of the research plan, a set of familiar semantic and alphanumeric stimuli will be presented to subjects as part of two covergent scaling exercises. The purpose of these tasks is to determine the representation of these stimuli in long term memory, as the arguments, predictions, and interpretations in later phases of the research plan depend upon such a determination. In PHASE 2 a micro-level assessment of intellectual components will be conducted (speed of encoding). Subjects will be presented these and novel stimuli (moving baseball images) at the minimum onset durations and interstimulus intervals necessary to encode them. If encoding operations can be differentiated on the basis of the structure of a stimulus' underlying representation, this would complicate notions of intelligence that are based on the neurological underpinnings of information processing constructs, as such constructs would be shown to be context- and stimulus- specific and not indicative of neural functioning in any direct sense. In PHASE 3 of the research plan, another micro-level assessment will be undertaken of three mechanisms governing the sequence of operations in retrieving information from semantic memory. "Semantic distance effects", "reverse distance effects", and the "same/different effect" will be explored as a function of the degree of elaborateness of a stimulus' representation. In PHASE 4 a macro-level assessment of intelligence will be carried out, focusing on complex thinking and reasoning skills. The goal here will be to determine the interrelationship between: a) complexity at a distance perdiction task, b) micro-level information processing parameters, and c) one traditional indicant of intellectual functioning, IQ. The reasoning tasks will be "driven" by algorithms of varying complexity and in novel vs familiar contexts. In PHASE 5, a bio-ecological model will be further developed to account for the findings from the four previous phases. Several empirical tests involving the complexity of expert and novice gamblers' thinking and reasoning skills will be carried out and the bio-ecological model will be evaluated and extended in light of these results. If time permits, PHASE 6 will be conducted. This is comprised of two sets of experiments that are as yet only partially formulated.